Marine Interpretation Message
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AGXX40 KNHC 090800

Marine Weather Discussion
NWS National Hurricane Center Miami FL
300 AM EST FRI DEC 9 2016

Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea,
and Tropical North Atlantic from 07N to 19N between 55W and 64W
and the Southwest North Atlantic including the Bahamas


MODEL PREFERENCE: Global model consensus. High confidence then
medium confidence next week.

The 06Z surface analysis shows the cold front extending from
south Florida southwest to 25N86W and west to 25N90W to 24.5N93W,
and south to inland Mexico near Veracruz. A dissipating front is
just to the south of the cold front from the Straits of Florida to
24N87W and to near 22N93W. Very strong high pressure of 1042 mb is
centered over the central U.S. with a ridge extending southward
over eastern Texas and along the coast of Mexico behind the cold
front. The associated pressure gradient is resulting in a quite an
extensive area of strong to near gale force northeast winds with
frequent gusts across much of the northwest and western portions
of the central gulf, while sustained north winds of strong gale
force intensity are observed west of the cold front in the
southwest gulf zone (GMZ023) and in the western portion of zone
GMZ017 per the 04Z Ascat pass. Ship with call sign "A8RHG"
reported northeast winds of 42 kt near location 26N97W near 06Z
with combined seas of 16 ft. NDFD wind and waveheights were
adjusted upward a little for the overnight period and to 12Z
Friday. Elsewhere across the gulf both buoys and the latest Ascat
pass depict fresh to strong northeast winds north of the cold
front and west of 84W, except for fresh northeast winds between
the cold front and dissipating stationary front and lighter winds
from the north and northeast in the gentle to moderate range east
of the cold front in the eastern Bay of Campeche and moderate to
fresh northeast to east winds between the dissipating stationary
front and the Yucatan peninsula and also the Yucatan channel. Seas
range from 10 to 17 ft in the far western gulf and southwest gulf
sections to 8 to 12 ft elsewhere north of 24N west of 87W. Seas
over the remainder of the gulf are in the 5 to 8 ft range except
for lower seas of 4 to 6 ft east of 84W.

Water vapor imagery shows ample upper level moisture streaming
eastward across much of the central and eastern gulf in a broad
upper level flow pattern across the region. The combination
of this flow and convergent surface winds is producing
scattered showers and isolated thunderstorms over much of the
central gulf zones GMZ019, GMZ015, GMZ021 and in portions
of zone GMZ023 and GMZ025. This activity will continuue into
most of the weekend. Reinforcing cold air moving southward into
coastal Texas and the lower Mississippi Valley will maintain the
northwest to north winds to the gale force range over the west
central and southwest portions of the Gulf near the coast of
Mexico from Tampico to Veracruz through this afternoon, then along
and Veracruz through Saturday afternoon as the aforementioned
strong high shifts eastward and weakens. Northeast to east winds
will be mainly in the strong to near gale force range outside the
gale force wind areas tonight across much of the central and
west-central gulf zones with fresh to strong northeast winds
elsewhere. On Saturday, winds diminish to fresh to strong over
much of the central gulf and become fresh northeast to east
elsewhere except for the gale force winds near Veracruz. These
winds then diminish to strong on Saturday night. Seas are forecast
to peak up to 20 ft in the southwest gulf behind the front
tonight, then subside to 14 ft on Saturday, to 12 ft Saturday
night and to 9 ft late Saturday night before subsiding further to
5 to 6 ft by Sunday afternoon. Seas elsewhere will subside to 4 to
6 ft by Sunday, and to 2 to 3 ft Monday night and Tuesday.

For the day 5 time frame (Tuesday) models are not in agreement
with the possibility of the next cold front to move into the
northern gulf. For time being will headline this next front as
approaching the gulf.

55W AND 64W...

MODEL PREFERENCE: Global model consensus. High confidence.

The 0218 Ascat pass showed a swath of mostly northeast winds to
the south of Hispaniola and southwest of Puerto Rico south to near
13N. Seas remain in the 7 to 9 ft range over the south central
Caribbean. Both buoy and Ascat data show moderate to fresh
northeast to east elsewhere east of 79W, and gentle to moderate
winds northeast winds west of 79W. Seas within these areas are in
the 6 to 8 ft range, except for 4 to 5 ft west of 79W and lower
seas of 2 to 3 ft north 18N west of Jamaica. A well-defined
surface trough, resembling an easterly wave is analyzed over the
eastern Caribbean near 69W as of 06Z moving west at about 10 to 15
kt. Scattered showers and thunderstorms east of the trough. This
activity is being further enhanced by a small upper-level low just
to its west at 16N71W.

A cold front will stall across the Yucatan Channel and far
northwest portions of the Caribbean by Saturday. Building high
pressure behind the front north of the area will support an
expanded area of strong trades over the most of the eastern and
central Caribbean. Winds through the Windward Passage and in the
lee of Cuba will increase briefly late Saturday as well. Models
still in pretty good agreement that the high pressure will slide
east, and reach from the central Atlantic through the Gulf of
Mexico, supporting moderate to fresh trades across the tropical
north Atlantic through the central Caribbean early next week, with
strong trades east of the Leeward Islands by Tuesday.


MODEL PREFERENCE: Global model consensus. High confidence.

Strong high pressure is surging eastward  from the Carolinas into
the western Atlantic behind a cold front currently extending from
31N73W to south Florida. The front will move eastward and reach to
roughly along 25N by Sunday, then stall near 22N by early next
week while undergoes dissipation. The strong high pressure will build
across the basin through Sunday, then shift eastward to the
eastern part of the basin by Tuesday in response to a weak
cold front that approaches the southeast U.S. Strong northeast
winds south of the ridge and to the north of the front will
encompass the area from 24N to 27N through the northern Bahamas by
early Saturday evening. As the high pressure shifts eastward,
these conditions will expand to much of the area south of 27N
through Sunday night, then shrink in coverage through Tuesday as
the pressure gradient slackens. Seas to 8 ft will persist through
Monday east of the Bahamas, then be confined to zone AMZ127 on
Tuesday as seas subside to 4 to 5 ft elsewhere east of the
Bahamas, and to 2 to 3 ft southwest of the Bahamas. The previously
mentioned cold front is expected to brush the far northern waters
late Monday into Tuesday. Presently, model guidance highlights
mainly fresh south to southwest winds ahead of this front, and
gentle to moderate west to northwest winds behind it. Seas of 5 to
6 ft are expected to be associated with the front, but may be a bit
higher if winds increase more than what the guidance indicates.


.WARNINGS...Any changes impacting coastal NWS offices will be
coordinated through AWIPS II Collaboration Chat, or by

     Gale Warning early today.
     Gale Warning early today.
     Gale Warning early today into today.
     Gale Warning early today.
.GMZ023...SW GULF S OF 22N W OF 94W...
    Gale Warning through Saturday afternoon.

55W AND 64W...



*For detailed zone descriptions, please visit:

Note: gridded marine forecasts are available in the National
Digital Forecast Database (NDFD) at:

For additional information, please visit:


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